Closed feed system for steamships



Aug. 6, 1929.

Filed Sept. 2'7, 1927 Patented Aug. 6, 1929.

UNITED :STATES PATENT OFFICE. 1

JAMES SIM, OF CATHCART, GLASGOW, SCOTLAND, ASSIGNOR TO G. & J. WEIR, LIMITED,

013 CATHOART, GLASGOW, SCOTLAND.

CLOSED FEED SYSTEM FOR STEAMSHIPS.

Application filed September 27, 1827, Serial No. 222,407, and in Great Britain November 10, 1926.

This invention consists in an improved closed feed system for steamships.

When a ship is titted with a closed feed system for the main driving units, it is very desirable to have the harbour auxiliaries working on a closed feed system in. harbour. This is particularly desirable in warships, which in general spend the major portion of their lifetimcin harbour. I r 10 tion allows this desideratum to be obtained.

The invention consists in a feed system for a steamship power plant, including both main and auxiliary steam motors. The arrange ment is such that the system is maintained closed whether both the main and auxiliary steam motors are in operation when the ship is at sea) or when only the auxiliary steam motor (or motors) is in operation (as when the ship is in harbour). The system comprises an arrangement and combination of elements which, with the functioning there of, will be explained and made clear by the following description and'the accompanying diagrammatic drawing.

claim.

a is an auxiliary engine,e. g. a steam turbine which is always running whether the ship is at sea or in port. Z) is the condenser for a. 0 is a tank arranged below the condenser I). The water of condensation flows from the condenser into this tank.

A water-extraction pump .2 of the centrifugal type withdraws feed water from the tank 0 andwhen the ship is in harbourdelivers it under a pressure of about QOpoundsper square inch above atmosphere along the pipe it direct to a harbour feed pump f which delivers it into the main feed waterconduit v and thence to one (or more) of the (main) boilers m. A small float d in the tank 0 controls a si'lpplementary feed valve 0 071 a pipe 72, which leads from a fresh water tank is to the condenser b and serves to admit supplementary feed water to the system in accord ance with the water level in the tank 0.

The control and action of the arrangement when the ship is in harbour are as follows Owing to the relative size of the he *bour auxiliaries and the main boilers, the latter may be regarded as of large water capacity so The present inven- The invention will be defined in the annexed that, under varying loads-i. e. harbour loads there Wlll be no appreciable, or at least very little, variation 1n the boiler water level. The

variation in the quantity of water delivered by the feed pump will therefore be small; a nd. this variation will be sufliciently met by the float-controlled supplementary feed valve.

A pipe 0 is provided connecting the pipe at with the main feed water conduit on the suction side of the main it'eed pump 10. A handcontrolled valve 6 is provided on this pipe. Valves 0 and s are provided on the pipe 71 on the suction and discharge sides respectively of the pump 7', or one or other only of these valves may be fitted. A valve a is placed on the conduit '0 on the discharge side of the pump w. i

Then the ship is running at sea, the valves r and s (or one of them) are shut, and the harbour feed pump is stopped: the valves 23 and '16 are open and the main feed pump run. The feed water therefore from the tank 0 is delivered by the water extraction pump into the main feed water conduit 1; on the suction side of the main feed pump. lVhen. the ship is in harbour, the valves 7' and s are open and the valves t and it shut.

It will be seen that, whether the ship is at sea or in port, the (lo-aerated condensate from the auxiliaries which exhaust into the condenser 6 passes in a- .closed feed system to the boilers.

Having thus described my invention, what I claim as new and desire to secure by Let'- ters Patent is y A feed system' for a steamship power plant, the system col'nprising a steam generator, an auxiliary engine, a condenser for the said auxiliary engine, a tank arranged below the said condenser, means whereby the condensate flows from the said condenser into the said tank, a main iced conduit, a water-extraction pump of the centrifugal type, acting to withdraw teed water from the said tank and deliver it into and along the said main feed conduit, a main feed pump on the said main feed conduit, a hand controlled valve on the discharge of the said feed pump, a harbour feed pump intended for use when the ship is in harbour. a pipe connecting the discharge of the said water-extraction pump Valve on this pipe, a pipe connecting the discharge of said water-extraction pump with the said main feed conduiton the suction side of the said boiler feed pump and a handcontrollod Valve on this pipe.

I hereby sign my nzune to this specification.

JAMES SIM. 

